stumpf



July 10, 1928; Re. 17,032

. J. STUMPF METHOD AND MEANS FOR DELIVERING PREHEATED FEEDWATER Original Filed May 2'7, 1925 5 Sheets-Sheet 1 July 10, 1928. Re. 17,032

J. STUMPF METHOD AND MEANS FOR fiELIVERING PREHEATED FEEDWATER Original Filed May 27, 1925 5 Sheets-Sheet 2 Izdenior: J5lzanm zan y WWW fliiOrrzey July 10, 19 28.

J. STUMPF METHOD .AND MEANS FOR DELIVERING PREHEATED FEEDWATER Sheets-Sheet 5 22 \{Al v E Julylo, 192s. Re. 17,032

J. STUM PF METHOD AND MEANS FOR DELIVERING PREHEATED FEEDWATER Original Filed May 27, 1925 5 Sheets-Sheet I 4 J. STUMPF METHOD AND MEANS FOR DELIVERING PREHEATED FEEDWATER July 10, 1928. Re. 17,032

Original Filed 2'? Sheets-Sheet 5 f'werdvr'.

named July 10, 1928.

UNITED STATES PATENT OFFICE.

JOELNN STUMPE. OF BERLIN, GERMANY.

METHOD AND MEANS FOR DELIVERING PREHEATED FEEED WATEE.

I Original No. 1,616,239, dated February 1, 1927, Serial No. 33,092, filedlay 27, 1925. and in Germany l llay 81, 1924:. Application for reissue filed Augult 25, 1927. Serial 1T0. 215,489.

This invention relates to an improved method for delivering preheated water to boilers or steam generators, more particularly high-pressure steam generators, by means of injectors, and the invention also embodies a convenient form of compound or mu'lti-stage injector apparatus for carrying the process into effect. The invention may be applied to locomotives, locomobiles or any form of steam generating plant.

It has long been recognized that steam injectors may be used to supply pro-heated water under pressure to a boiler, and the )ractice hitherto has been to use one stage 1n steam and Water and to limit the temperature of the feed or the inlet water to the injector so as to ensure safe suction and eflicient injector action b quick condensation of the steam. It has )een assumed that in connection with a single stage injector there was a maximum temperature at which the deed water could be supplied to the injector Engine by Dr. J. Perry 1900, page 615.)

therein.

As is generally known, the total intrinsic ener of the steam entering the injector is utilized in part to raise the kinetic energyv of the combined feed water and condensed injector steam and in part to raise the temperature of this combined stream. This kinetic energy is subsquently transformed into pressure energy in the diffuser or tapered delivery pipe of the injector and in this way thefeed -water is forced into the boiler against the working pressure of the fluid I have now found that by compounding injectors in what is analogous to the reverse manner in which prime movers are com pounded, the top limit of feed temperature as hitherto understood can be considerably ,exceeded, and I thus recover more heat enno longer a temperature beneath 212 F. the

boiling point at atmospheric pressure, but if the commingled stream is at a pressure of 2 atmospheres absolute the temperature would be something less than 250 F. If a third stage is added and the delivery from the second stage is at say 5-atmospheres absolute, the top limiting temperature will be something less than 300? F.

When applied to a steam power plant, the i invention ofl'ers advantages additional to these associated immediately with the com- .pounding or staging of the injector. As is well known, the auxiliaries, such for example as the feed pumps, air pumps or lighting power plant in a locomotive or other power units, do not use the steam expansively, or do so only to a small degree. There is thus provided ready to hand a plurality of sources of supplyof steam at different pressures. It is not, therefore, necessary to use high pressure steam ,in each stage of the injector, but the first stage may use low pressure steam and each successive stage may be supplied with a successively higher pressure steam. In this way, the injector stage does not mere] upgrading of t e temperature and pressure of the feed water, but also as a second expansion stage of the incompletely expanded duction, and those due to friction of the fluid in the passages of the injector. By arranging the injector in stages in the manner set forth, the velocities in the injector nozzles are those due to the difference inhead between the incoming water pressure and the outgoing water pressure. By increasing the pressure in stages the velocity is in all stages retained within reasonable limits. When it function as a stage in the that a is recollected that the frictional losses increase in proportion to v where '0 is the velocity of the stream, it will be recognized so the pumping action is materially improved by this arrangement of the injector in stages in addition to't'he improved heating action.

If more stress yet is laid on the heating action it may be done by damaging the pumping action, for example, by artificial leakage, thereby increasing the steam consumption and consequently the heating action. I The invention will be more readily understood from the following description, reference being made to the accompanying drawings in which i Fig. l is a diagram showing my improved process for supplying feed water to a steam generator by means of a multi-stage injector apparatus.

- Fig. 2 is a section of a convenient form of multi-stage injector.

,1 Fig. 3' is a section taken at right angles to that shown in Fig. 2.

Fig. 4 is aplan view in section on the line AB of Fig. 2.

Fig. fi'shows a device to draw ofl exhaust steam from common steam cylinders at higherpressure.

Fig. 6 shows a detail of a steam piston suit-able therefor. y

Fig. 7 shows a 3-stage injector, the first stage operated by exhaust steam, .thelast two stages operated by live steam.

In carrying the invention into eifect, steam from a generator G passes by steam mains M-to any form of prime mover plant or other apparatus where it is used expansively as. indicated in the steam diagram D. Three injectors 11", 1 1 are connected up, as regalrds their steam supply, to points in the plant where the boiler-steam has been used or partially used expansively. The injector 1 isconnected up to a source of steam supply at a low prcssure for example, the exhaust'steam ,from the main engine. This injector may draw water from a cold sup ply. The'steam in this injector will only have a very small range of pressure fall, and the effect will be principally to raise the temperature of the feed to the next injector stage 1" which receives the water at increased pressure, say P The steam supplyto the injector-stage 1? will be expanded,

down to the pressure P and not to atmospheric pressure, whereby the kinetic energy of the combined stream of inlet water and condensed steam in 1Qis increased by an amount corresponding to the pressure difference between P", the outlet pressure from injector 1", and P, the outlet pressure from injector 1. The temperature of thecombined stream from 1 is further increased by the condensation of the injector steam 1" and mum and minimum this combined stream at higher pressure and temperature passes to the next stage 1.

Stage 1 may be operated by live steam or by steam'ofab0ut live steam pressure. This final stage'may force the water through pipe N into theboiler with an increased temperature which may be not far below the boiling temperature of the boiler.

It will be understood that any desired number of stages may be interposed. The various sources of supply of steam of different pressure may be obtained from widely difl'erent kinds of plant, thus inthe case of turbines, the injector steam may be Withdrawn from the turbine case at difi'erent stages in the expansion of the steam.

The heating action is increased the more exhaust steam and the more head is used for this exhaust steam, which latter may imperil the safe suction action to some extent. Within this limit exhaust should be used as much as-qpossible. The same holds true for the interposed stages in which operating steam has been used with a partial drop of pressure in other Steam motors.

p Also the exhaust steam of the first stage should have some pressure and not too large a head to work against this for ensuring a safe suction. Exhaust steam of some pressure may be secured by the device shown in Figure 5. The two cylinders Z Z of a locomotiveare tapped in the middle of the p ston stroke. The nozzle-like tap holes D D and conductors d and d lead the steam to-- gether ejector-like, thus drawing ofi' exhaust steam almost entirely expanded by the steam flowing out under some pressure from the other cylinder. The advance in opening the exhaust nozzles may be from 30-40% of the piston stroke. This advance may be decreased by suitable laps .1 at the pistons K brought-on the closing-piston o'fthevalve V by the pipe b. A' spring under. this piston will open valve V under'insuflicient pressure of receiver A a'ndwill admit live steam through pipe X,- thus maintaining always a certain pressure in the receiver. A. which can readily .be adjusted by adjusting the spring in valve V.

In modern injectors the action is not readily adjustedthat is to say, there is onl a relatively small range bet-ween the maxideliveries against a given pressure.

This is owing to the fact that in injectors steam' adjusted simultaneously, and

as hitherto used, the adjustment has been effected by throttling the steam.

In order to obtain the bestaction of the injector, the cross section of the steam nozzle, the water nozzle and the diffuser should alwa 5 remain in a definite relation to one anotli er, if possible under constant widening of the steam nozzle and the diffuser. H An alteration of the steam supply disturbs the mutual relations of the cross sections of the parts mentioned, and this has the effect of seriously limiting the degree of adjust-ability orrange of adjustment of the injector.

These difficulties associated with ordinary injectors are accentuated .when dealing with a multi-stage injector but they may be overcome in both single stage and multi-stage injectors by simultaneous adjustment ofthe steam and water nozzles, and preferablyalso of the diffuser. I

In multi-stage injectors the various adjustments mi ht be made separately for each stage, but it is preferable that all the injectors which are arranged in series should be iroportionately by a single operatingmemlier.

Referring to Figure 2, the invention is here shown applied to a three stage injector adapted to carrying out the process described with reference to the diagram in Figure 1. The inlet water to the first stage of the injector enters by the pipe a and is drawn by the steam issuing from the nozzle 0' into a contracting and expanding mixer and diffuser p. The steam conveniently from a low pressure source, enters by the ports e and the water by port y both of which are controlled by the cylindrical part of the slidable nozzle 0'. Thiscylindrical part is prevented from turning by a notch n, Fig. 3, and internally threaded and is engaged by a thread on the end of a rotatable rod, f which passes upwards through a suitable stuffin box 6 and is supported in a bush h carrie by the frame 7; The rod or spindle f has keyed on to it a gear wheel 9 which gears with the gear wheel g on a central rod f. The rod f 'is arranged similarly to the rod f and operates the nozzle body (2 which controls ports 6 and the steam nozzle 0 and the water nozzle 3 of the second injector stage. The spindle f passes through a bushing h, and has a hand wheel f keyed thereon. The gear wheelg? engages. a third gear wheel g fixedon a spindlef, housed in a bushing k and adapted in a manner similar to the spindle f to con trol a nozzle body d which opens or. closes steam ports for the supply of steam to the third steam nozzle 0 and the water port 3 of the third injector stage. The spindle f is also in threaded engagement with the yoke, z' for controlling the diffusers or mixing tubes. 'It will be understood that the several threaded engagements are so arpassing therethrough an the. normal increase 1n pressure at which they are intended to work.

Tapered control rodsk in [a project upwardly through the expanding or diffuser part of the mixing tubes for the purpose of controlling the free area at the most constricted point of the mixing and diffusin tubes as well as the taper ratio of the di fuser. The control members 7:, k, is have valves m, m m fixed on them which are adapted, when the injector has been started up, 'to close successively and thus shut off the overflow which escapes by the valve 1) at the bottom left hand side of Figure 2. It will be seen from Figure 2..that the valves m, m, m are at different and increasing heights, above their overflow ducts. By moving the rodsk', k simultaneously downwards, the valve m, first closes the overflow from the low pressure injector so that the delivery from this injector then takes place through the ports 0' to the chamber b which is the inlet chamber to the second injector stage. A further downward movement allows the valve m to close its overflow-duct, whereu on the delivery from the second injector ta, es place through the ports 0 to the chamber 6 which is the inlet chamber of the third injector stage. A still further downward movement allows "the valve m to close its overflow-duct whereupon the discharge from the third injector stage takes place through ports .03 and the delivery valve '1) from the multi-stage njector.

The downward movement described 1s effected by extending the rods 70', 10 It downwards through the overflow chamber 8 and stuffin boxes9 to be coupled to a spider. frame i. cross, and the armsat, right angles to those shown in Fi ure 2 (see Figure 3) are connected by rods 1" to a yoke i which engages a thread on the central spindle f In this way when the hand wheel 1 is rotated, the nozzle bodies (2, d, d are simultaneously operated; the steam nozzles c", 0?, c and waternozzles y, f, y are operated to constrictions and tapers of the mixing and dif fuser tubes'are adjusted by the controlling members In, k,'k and the overflow valves e spider i is in the form of a m, m, m are operated. It will be understood that after the valves mf, m m have closed their overflow ducts, a further downward movement of the yoke i is combined with an upward movement of the above described cylindrical parts thereby increasing the steam admission area, the water inlet area and the area of the constricted part of the mixing and diffuser tubes;

If the exhaust steam pressure isvery low and does-not ensure safe suction for the first stage, it may be advisable toopen the overstages only as described above, the en'ergeti-- cal live steam will drawthe water through the first stage and second stage with all safety, so that any overflow device for the first stage is superfluous and exhaust steam of very low pressure can be used for the first stage. It will be noticed, that both 'live steam "chambers of the last two stages are connected.

The adjustment of the steam nozzle can be furthermore improved by using a needle. If a needle is used like that of the difi'user for decreasing the constricted part of the steam nozzle if possible with suitable adjustment of the widenin of, the steam nozzle it would give a better e ect.

What I claim is i I 1. The method, of delivering preheated feedwater, which' consists in utilizing the injection action of exhaust steam operating for different stages, the said exhaust steam being of different pressures for the-different stages.

2. The method of delivering preheated feedwater, which consists in utilizing the injection action of live steam, and exhaust steam operating". for diiferent stages, the steam used ins'ome stages bein steam that has done work but not expan ed down to the exhaust pressure. of thecylinders.

The -method of deliverin'g v preheated w feedwater, which consists inutilizing the injection action of steam operating for different stages, the live steam operating in some stageor stages and exhaust steam at different pressures operating for other stages. I

4. The method of delivering preheated feedwater, which consists in utilizing the injection action of steam operating for. different stages and simultaneously controlling the water inlet for each stage- 5. The method of delivering preheated feedwater, which consists in utilizing the injection action of steam operating for different stages and simultaneously and proportionately controlling the water inlet for each stage. I I

6. Means for delivering[preheated feedwater, comprising a multi-stage injector operating with exhaust steam at different pressures in diflerent stages.

7. Means for. delivering preheated feedwater, comprisingfa multi-stage injector operating with exhaust steam at different pressures different stages and live steam" in other stage or stages.

8. Means for delivering preheated feedwater, comprising a 'multi-stage injector and operatin means for the simultaneous control of t e water inlets of the several stages.

,9. Means fordelivering preheated feedwater, comprising a multi-stage injector and operating means for thesimultaneous control of the steam and water inlets of the several stages. I

10. Means for delivering preheated feedwater comprising a multi-stage injector, and

operating means for the simultaneous control of the water inletsand difl'users of the several stages. I I

11. Means for delivering preheated feedwater, comprising a multi-stage injectoigin combination with a plurality of cylinders and means for bleeding steam, which has already done partial. work, from one cylinder, means for utilizing the injector action of this steam to draw exhaust steam from another cylinder, and means for utilizing the combined steam thus drawn from the different cylinders for operating one stage of the-multi-stage injector. I I

12. Means for delivering preheated feed-. water, comprising a multi-stage' injector and means for proportionally adjusting the cross-sections of the steam water and diffuser. nozzles-of the several injectonstages.

13. Means for delivering preheated feedwater, comprising a multistage injector and.

means for simultaneously controlling all the injector stages and for proportionally adjusting the cross-sections of the steam, water and difiuser nozzles of the several injectors. 1

14. Means for delivering preheated feedwater, comprising an injector having steam and water nozzles and a difluser, and means for the simultaneous adjustment of said nozzles.

15. Means for delivering preheated feedwater, comprising an injector havin steam and water nozzles and a difiuser, an means for the proportional adjustment of said nozzles.-v e

16. Means for delivering preheated feedwater, comprising an injector havin steam and water nozzles and a difiuser, an means for the adjustment of said nozzles and the diffuser. 1

17. Means for delivering preheated feedwater, comprising an injector having steam and water nozzles and a diffuser, and means for the simultaneous adjustment of said nozzles and the diffuser.

18. Means for delivering preheated feedwater, comprising an injector having steam and water nozzles and a diffuser, and means for the simultaneous and proportional adjustment of said nozzles and the diffuser.

19. Means for delivering preheated feedwater, comprising an injector having steam and water nozzles, a diffuser providing a J OHANN STUMPF. 

